1. Field of the Invention
The present invention relates generally to ink cartridges comprising a film which defines at least a portion of an ink chamber.
2. Description of Related Art
A known ink cartridge is configured to be mounted to and removed from an inkjet recoding apparatus. The known ink cartridge has an ink chamber configured to store ink, and when the ink cartridge is mounted to the inkjet recording apparatus, ink is supplied from the ink chamber to the inkjet recording apparatus. The ink chamber is defined by a frame and a pair of films adhered to opposite side faces of the frame.
The frame has a substantially flat, hexahedron shape having six faces. The frame has openings formed through two opposing faces which have the largest area among the six faces, and the openings are covered and closed by a corresponding one of the films adhered to the frame. The frame also includes an ink supply opening configured to supply ink from the interior of the ink chamber to the exterior of the ink chamber, and an air intake opening configured to draw air into the ink chamber. When the ink cartridge is mounted to the inkjet recording apparatus, ink in the ink chamber is supplied to the inkjet recording apparatus through the ink supply opening, and air flows into the ink chamber through the air intake opening.
Ink droplets may adhere to an inner wall surface of the frame when ink is gradually consumed. The ink cartridge may have walls or ribs extending in the gravitational direction, and ink droplets may be guided downward along the walls or the ribs. Nevertheless, when at least a portion of ink chamber is defined by films, it is difficult to provide walls, ribs, or the like on the inner surfaces of the films. Consequently, ink droplets adhering to the inner surfaces of the films do not run downward, and a substantial amount of ink may remain on the inner surfaces of the films.